降雨对大柏舍地电台地电阻率观测的影响

选取大柏舍地电台2011—2019年地电阻率观测数据和降雨量资料,分析降雨对地电阻率观测的影响,利用影响系数理论,对结果进行分析探讨。结果表明,由于大柏舍地电台表层介质影响系数较小且为负值,小幅降雨对该台地电阻率短期影响不明显,仅自然电位差受到干扰;大范围强降雨时,地电阻率和自然电位差均受到影响;因ZD8B仪地电阻率观测系统架空线路漏电,导致EW向分量呈阶降变化,且比用于背景场观测的ZD8M仪变化幅度大。

Analysis of rainfall effects on earth resistivity observation at Dabaishe station

By selecting earth resistivity observation and rainfall data from 2011 to 2019 at the Dabaishe station, we analyze the effects of rainfall on earth resistivity observations and discuss the results using the influence coefficient theory. It shows that because the influence coefficient of the surface layer at the Dabaishe station is small and negative, the short-term effect of small rainfall on the earth resistivity observation is not obvious and only the spontaneous potential difference is disturbed. When a large-scale heavy rainfall occurs, both the earth resistivity and the spontaneous potential difference observations are affected. The EW-component observation of earth resistivity of ZD8B shows step reductions due to the leakage between lines; its variation amplitude is bigger than that of ZD8M.